At the same time, crop residues were taken from soil
surface in both years to evaluate total amounts of nutrients
immobilized in residual biomass. Samples were taken from
three randomly chosen 1 m2 areas and nutrient chemical
evaluation was based on procedures described by Bataglia
et al. (1983). The DM of residues covering the first ratoon
was 13.9 t ha-1, whereas in the second ratoon it was 18.0
t ha-1. Chemical analyses of residues from first ratoon and
second ratoon showed the following respective results: N
= 3.5 and 6.5, P = 0.5 and 0.4, K = 1.2 and 0.3; Ca = 3.1
and 2.7, Mg = 0.7 and 0.9, and S = 1.6 and 0.7 g kg-1.